Version: 1.0.x

Flow Example

In this configuration:

API requests to api.com/* are managed based on both monthly and daily quotas.
Requests are filtered by the x-lunar-consumer-tag header to differentiate between production and staging traffic, with each environment having distinct quotas.
Production traffic is prioritized over staging traffic, with production requests receiving higher priority (1) and staging traffic receiving lower priority (2).
Requests that exceed the limits or queuing capacity will receive a 429 Too Many Requests response.

Flow Configuration

/etc/lunar-proxy/flows/flow.yaml
name: MonthlyAndDailyLimit-Prod

filter:
    url: api.com/*
    headers:
      - key: x-lunar-consumer-tag
        value: production
      - key: x-lunar-consumer-tag
        value: staging

processors:
  QueueLimiter:
    processor: Queue
    parameters:
      - key: quota_id
        value: LimiterSecond
      - key: ttl_seconds
        value: 12
      - key: queue_size
        value: 10
      - key: priority_group_by_header
        value: x-lunar-consumer-tag
      - key: priority_groups
        value: 
          production: 1
          staging: 2

  LimiterProd:
    processor: Limiter
    parameters:
      - key: quota_id
        value: LimiterProd

  LimiterStaging:
    processor: Limiter
    parameters:
      - key: quota_id
        value: LimiterStaging

  ProdFilter:
    processor: Filter
    parameters:
      - key: header
        value: x-lunar-consumer-tag=production

  GenerateResponseTooManyRequests:
    processor: GenerateResponse
    parameters:
      - key: status
        value: 429
      - key: body
        value: "Quota Exceeded. Please try again later."
      - key: Content-Type
        value: text/plain

flow:
  request:
    - from:
        stream:
          name: globalStream
          at: start
      to:
        processor:
          name: QueueLimiter

    - from:
        processor:
          name: QueueLimiter
          condition: blocked
      to:
        processor:
          name: GenerateResponseTooManyRequests

    - from:
        processor:
          name: QueueLimiter
          condition: allowed
      to:
        processor:
          name: ProdFilter
      
    - from:
        processor:
          name: ProdFilter
          condition: hit
      to:
        processor:
          name: LimiterProd
          
    - from:
        processor:
          name: LimiterProd
          condition: above_limit
      to:
        processor: 
          name: GenerateResponseTooManyRequests

    - from:
        processor:
          name: LimiterProd
          condition: below_limit
      to:
        stream:
          name: globalStream
          at: end

    - from:
        processor:
          name: ProdFilter
          condition: miss
      to:
        processor:
          name: LimiterStaging

    - from:
        processor:
          name: LimiterStaging
          condition: above_limit
      to:
        processor: 
          name: GenerateResponseTooManyRequests

    - from:
        processor:
          name: LimiterStaging
          condition: below_limit
      to:
        stream:
          name: globalStream
          at: end

  response:
    - from:
        processor:
          name: GenerateResponseTooManyRequests
      to:
        stream:
          name: globalStream
          at: end
  

Flow Parameters

Parameter	Example Value	Description
`name`	`MonthlyAndDailyLimit-Prod`	The name of the flow, used to identify it in configurations.
`filter.url`	`api.com/*`	Filters API requests based on the URL pattern for which the flow applies.
`filter.header.key`	`x-lunar-consumer-tag`	The header key used to differentiate between traffic types (e.g., production, staging).
`filter.header.values`	`['production', 'staging']`	The values that the header must match to apply specific limits (i.e., production and staging).
`processors.QueueLimiter.processor`	`Queue`	Defines the processor responsible for managing the request queue and handling priorities.
`processors.QueueLimiter.parameters.key`	`quota_id`, `ttl_seconds`, `queue_size`, `priority_group_by_header`, `priority_groups`	Parameters for configuring the queue's quota, time-to-live (TTL), size, and priority logic.
`processors.LimiterProd.processor`	`Limiter`	Applies rate limiting to production traffic, using the defined quota for production.
`processors.LimiterStaging.processor`	`Limiter`	Applies rate limiting to staging traffic, using the defined quota for staging.
`processors.ProdFilter.processor`	`Filter`	Filters production traffic based on the `x-lunar-consumer-tag` header (set to `production`).
`processors.GenerateResponseTooManyRequests.processor`	`GenerateResponse`	Generates a response when the request exceeds the rate limit or the queue limit, returning an HTTP 429 response.
`flow.request.from.stream.name`	`globalStream`	The input stream where the request flow starts.
`flow.request.to.processor.name`	`QueueLimiter`, `ProdFilter`, `LimiterProd`, `GenerateResponseTooManyRequests`, etc.	The processors to which the request flow is routed, depending on whether it is blocked or allowed.
`flow.response.from.processor.name`	`GenerateResponseTooManyRequests`	Generates the response for requests that exceed limits (429 response).
`flow.response.to.stream.name`	`globalStream`	The output stream to which the response is sent.

/etc/lunar-proxy/quotas/quota.yaml
quota:
  id: LimiterMonth
  filter:
    url: api.com/*
  strategy:
    fixed_window:
      max: 10000000
      interval: 1
      interval_unit: month
      monthly_renewal:
        day: 1
        hour: 11
        minute: 0
        second: 0
        timezone: UTC

internal_limits:
  - id: LimiterSecond
    parent_id: LimiterMonth
    strategy:
      fixed_window:
        max: 1
        interval: 1
        interval_unit: second

  - id: LimiterProd
    parent_id: LimiterMonth
    filter:
      headers:
        - key: x-lunar-consumer-tag
          value: production
    strategy:
      fixed_window:
        max: 100000
        interval: 1
        interval_unit: day

  - id: LimiterStaging
    parent_id: LimiterMonth
    filter:
      headers:
        - key: x-lunar-consumer-tag
          value: staging
    strategy:
      fixed_window:
        max: 20000
        interval: 1
        interval_unit: day
      spillover:
        max: 100

Quota Parameters

Parameter	Example Value	Description
`quota.id`	`LimiterMonth`	The unique identifier for the monthly quota applied to the flow.
`filter.url`	`api.com/*`	Filters API requests based on the URL pattern for which the quota applies.
`strategy.fixed_window.max`	`10000000`	The maximum number of requests allowed within the specified interval (monthly quota).
`strategy.fixed_window.interval`	`1`	The interval duration for which the requests are counted.
`strategy.fixed_window.interval_unit`	`month`	The unit of time for the interval, in this case, a month.
`internal_limits.id`	`LimiterSecond`, `LimiterProd`, `LimiterStaging`	The unique identifiers for internal limits nested within the parent quota.
`internal_limits.parent_id`	`LimiterMonth`	Links the child quotas to the parent monthly quota.
`internal_limits.strategy.fixed_window.max`	`100000`, `1`, `100000`, `20000`	The maximum number of requests allowed within each child quota (daily, per second, production, staging).
`internal_limits.filter.header.key`	`x-lunar-consumer-tag`	The header used to differentiate between production and staging traffic.
`internal_limits.strategy.spillover.max`	`100`	The spillover limit for handling requests beyond the quota (applies to the staging environment).

Flow Configuration​

Flow Parameters​

Quota Parameters​

Flow Configuration

Flow Parameters

Quota Parameters